Recent years have seen the increasing use of gonadotropin therapy for a variety of purposes. We have also seen the successfl in vitro fertilization of human ova. Yet, considering the magnitude of usage and potential of these techniques we know very little of the cytogenetic effects of such treatment on the gametes and the offspring which result. The proposed project will utilize nonhuman primates of two species to ascertain the cytogenetic effects of fertilization of young or old ova, the effects of in vitro matuation and fertilization, of ovulation induction and spontaneous ovulation after inhibitory treatment, with particular reference to chromosome analysis. We will utilize techniques which have been developed in our laboratory in the past several years and these include the laparoscopic prediction of ovulation time, laparoscopic aspiration of follicles, in vitro fertilization and culture, and chromosome analysis of ova and zygotes. These studies will provide informaton on chromosomal normalcy or damage during such manipulations, especially as such changes may exert a teratogenic effect on the potential offspring. Such work will be of significance when evaluating teratogenic effects (if any) of gonadotropin-induction of ovulation in women and when eventually, attempts are made to transfer an in vitro fertilized human ovum back to a recipient mother.